The present disclosure relates generally to environmental control systems, and more particularly, to a condensing furnace for environmental control systems.
Environmental control systems are utilized in residential, commercial, and industrial environments to control environmental properties, such as temperature and humidity, for occupants of the respective environments. The environmental control system may control the environmental properties through control of an airflow delivered to the environment. For example, a heating, ventilation, and air conditioning (HVAC) system may route the airflow through a condensing furnace having multiple heat exchangers prior to delivery to the environment. The heat exchangers absorb heat from the exhaust to heat the airflow. The use of multiple heat exchangers increases the overall efficiency of the condensing furnace due, in part, to recovery of a substantial amount of heat from the exhaust. Extraction of the heat from the exhaust gas by multiple heat exchangers may result in condensation of moisture from the exhaust gas. The condensed moisture is removed from the HVAC system via a drainage system. However, certain environmental conditions may affect removal of the condensed moisture through the drainage system. For example, in cold weather conditions when the temperature is at or below 0° Celsius (C) (32° Fahrenheit (F)), the condensed moisture may solidify (e.g., freeze) within the drainage system. This may result in blockage of the drainage system, thereby affecting operation of the HVAC system.